The present invention relates to a radiation plate structure which allows each radiating plate to be securely picked up from within a magazine of radiating plates stacked and mounted in a predetermined way in an automatic mounting process of the radiating plate for semiconductor devices, and a method for manufacturing semiconductor devices using the same structure.
At present, the manufacturing process of semiconductor devices is fully automated, and any trouble occurring in one step in a consecutive working process may stop the later steps, interfering with a manufacturing plan, giving rise to a severe problem. FIG. 5 is a cross-sectional view of a semiconductor device with radiating plate which is a Flip Chip BGA (Ball Grid Array) structure that has been conventionally manufactured, and FIGS. 6A to 6E are views showing a manufacturing process of the semiconductor device with radiating plate as shown in FIG. 5. In FIG. 5, reference numeral 1 represents a BGA substrate formed with a pattern of copper foil between multi glass layers (not shown) and hardened with epoxy resin, the pattern on one surface of the BGA substrate 1 and a terminal of an integrated circuit (not shown) for the semiconductor chip 2 being connected via a solder bump 3, and sealed by an under fill resin 4. And external electrodes 5 having a solder ball connected to the pattern are arranged in a matrix form on the other surface of the BGA substrate 1. Reference numeral 6 represents a protection ring attached by a thermosetting epoxy resin 7 on one surface of the BGA substrate 1, surrounding the semiconductor chip 2, and made of a metal such as copper, ceramic, or resin, the other surface of the protection ring 6 being bonded to a radiating plate 8 by a thermosetting epoxy adhesive 9, and the back face of the semiconductor chip 2 being bonded to the radiating plate 8 by a heat radiating resin 10 to constitute a semiconductor device 11 with radiating plate. And the heat produced within the semiconductor chip 2 and the BGA substrate 1 is transmitted via the radiating resin 10 to the radiating plate 7 and radiated to the outside.
In the semiconductor device 11 with radiating plate as above constituted, a task of attaching the radiating plate 8 to the semiconductor chip 2 is performed in such a way that the thermosetting epoxy adhesive 9 is applied on one surface of the radiating plate 8 where the protection ring 6 is bonded (FIG. 6A), the other adhesive face of the thermosetting epoxy adhesive 9 being pasted with a protection tape 12 of solid and flat shape which is made of polyethylene terephthalate film material (hereinafter referred to as a PET film material) which can be easily peeled off, to constitute a radiating plate structure 15 consisting of the radiating plate 8, the thermosetting epoxy adhesive 9 and the protection tape 12 as one piece, this radiating plate structure 15 being stacked successively within a magazine of an automatic mounting machine of radiating plate (not shown) (FIG. 6B), as shown in FIGS. 6A to 6E. On the other hand, the semiconductor chip 2 is attached on one surface of the BGA substrate 1 via the solder bump 3 and sealed by the underfill resin 4, and the protection ring 6 is attached by the thermosetting epoxy adhesive 7, surrounding the semiconductor chip 2, the radiating resin 10 being applied on the back face of the semiconductor chip 2 (FIG. 6C). And each radiating plate structure 15 within the magazine is picked up one by one by the automatic mounting machine of radiating plate, its protection tape 12 is peeled, and bonded to the semiconductor chip 2 and the protection ring 6 (FIG. 6D). Thereafter, the thermosetting epoxy adhesives 7, 9 and the radiating resin 10 are cured at 150 xc2x0 C. for four hours, and the external electrodes 5 are attached, to complete the manufacture of the semiconductor device 11 with radiating plate.
However, as seen from FIG. 7 which illustrates the occurrence of a malfunction in picking up the radiating plate, when the radiating plate structure 15a within the magazine is picked up by the automatic mounting machine of radiating plate, there occurs a phenomenon that the protection tape 12a is peeled and electrified, upon being separated from the radiating plate 8b of the radiating plate structure 15b directly below and joined together, to adsorb electrostatically the radiating plate 8b to lift the radiating plate structures 15a, 15b together, resulting in a problem that the radiating plate 8a can not be smoothly mounted to impede the productivity.
This invention has been achieved to resolve the aforementioned problems in the conventional example, and provides the radiating plate structure which allows to pick up securely the radiating plate one by one from within the magazine of the radiating plate mounting machine, and mount smoothly the radiating plate, in the automatic mounting process of the radiating plate for the semiconductor devices, and a method for manufacturing semiconductor devices using the same structure.
A radiating plate structure according to this invention, containing a radiating plate bonded on a protection member surrounding a semiconductor chip mounted on a substrate, comprises the radiating plate, an adhesive coated on a face of the radiating plate where the protective member is bonded, and a protection tape pasted with the adhesive, made of a material which can be easily peeled off this adhesive on which it is pasted and formed with a junction area reduction portion for reducing the junction area with the surface of a partner member to be joined on its non-pasted side.
Also, the junction area reduction portion is a projection which is projected on the non-pasted side of the protection tape to be pasted with the adhesive on the radiating plate.
Also, the junction area reduction portion is a through hole opened through the protection tape to be pasted with the adhesive on the radiating plate.
A method for manufacturing semiconductor devices according to this invention, a semiconductor device having a radiating plate bonded on a semiconductor chip mounted on a substrate and a protection member surrounding this semiconductor chip, includes a step of stacking the radiating, plate structure within a magazine of a radiating plate mounting machine, and a step of picking up each radiating plate structure stacked thereon, peeling its protection tape, and mounting the radiating plate at a predetermined position of the semiconductor device.
Also, the junction area reduction portion is a projection which is projected on the non-pasted side of the protection tape to be pasted with the adhesive on the radiating plate.
Also, the junction area reduction portion is a through hole opened through the protection tape to be pasted with the adhesive on the radiating plate.
Herein, the junction area reduction portion is a generic name encompassing the projection and the through hole.